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coa

Page 21 of 32 · 749 questions tagged coa.

749 questions · sorted by votes · page 21 of 32

14 votes5 answers23k views
Would you re-test liraglutide after ten weeks at 25 °C, or accept the original certificate?

For reference: liraglutide · ten weeks · 25 °C. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit stopping…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

832 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by samir_bennani 13k · 18 months ago
14 votes5 answers21k views
Has anyone independently verified a WWB dulaglutide batch COA?

Numbers first: WWB · dulaglutide. I would rather be corrected now than propagate something wrong. I am specifically not interested in a testimonial; I am interested…

vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
asked by bounty_hunter_q 18k · 21 months ago
14 votes5 answers18k views
What would you ask Qingdao Sigma Chemical before a first order that they cannot fake?

I am comparing three suppliers on documentation rather than on price. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have…

vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
asked by oona_kekkonen 16k · 11 months ago
14 votes 5 answers16k views
What does a date of analysis on an HJ report change about how I read it?

The particulars: date of analysis · HJ. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am…

coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by second_lot 11k · 19 months ago
14 votes 2 answers16k views
Would you re-test tirzepatide after ten weeks at room temperature, or accept the original certificate?

The particulars: tirzepatide · ten weeks · room temperature. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

832 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by juliette_farnese 12k · 14 months ago
14 votes 5 answers16k views
What does a 99.4% purity with a list of related substances attached let me conclude?

The specifics, since they change the answer: 99.4% · list of related substances. I have the document in front of me and I can read the numbers. What I cannot do is…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by liam_bracken 12k · 2.0 years ago
14 votes 4 answers16k views
How do I reconcile 97.6% from Janoshik with 97.1% from the supplier?

What I have: 97.6% · Janoshik · 97.1%. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by eighty_six_hours 16k · 9 months ago
14 votes5 answers16k views
How do I read an impurity table on a retatrutide certificate against the 98.2% headline?

Stated plainly: retatrutide · 98.2%. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far, for the…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by plunger_stop 18k · 8 months ago
14 votes0 answers15k views
What does a 98.4% purity with a sampling plan attached let me conclude?

Setup, so nobody has to ask: 98.4% · sampling plan. I would like help reading this properly rather than being told what conclusion to reach. I have the full report…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by rukhsana_iqbal 14k · 17 months ago
14 votes 5 answers14k views
How do I trace a Homopeptide lot number back to a synthesis date?

The lot number on the vial matches the certificate, which at least rules out the easy problem. I have done this once and I suspect I got away with it rather than got…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by anouk_desmet 18k · 7 months ago
14 votes 5 answers14k views
What does a 95.2% purity with a list of related substances attached let me conclude?

The specifics, since they change the answer: 95.2% · list of related substances. I have the document in front of me and I can read the numbers. What I cannot do is…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by amara_nwachukwu 41k · 5 months ago
14 votes 3 answers12k views
What does a 97.1% purity with a chromatogram attached let me conclude?

For reference: 97.1% · chromatogram. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am being…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by petra_hovland 42k · 21 months ago
14 votes5 answers11k views
What does 98.8% purity on a C4 column actually tell me about an orforglipron vial?

Concretely: 98.8% · a C4 column · orforglipron. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by dmitri_savchuk 17k · 15 months ago
14 votes 5 answers11k views
What does a date of analysis on a Homopeptide report change about how I read it?

The particulars: date of analysis · Homopeptide. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that…

coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by coring_risk 17k · 22 months ago
14 votes0 answers9.4k views
What does 99.1% purity on a C8 column actually tell me about a tirzepatide vial?

Numbers first: 99.1% · a C8 column · tirzepatide. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by orla_sheridan 14k · 2.1 years ago
14 votes 4 answers8.9k views
Is a lot-specific certificate from KP sufficient basis to skip independent testing?

What I am working with: lot-specific certificate · KP. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

445 questions
asked by ahmed_zerouali 19k · 4 months ago
14 votes 5 answers7.9k views
What does identity confirmation by mass spectrometry add for semaglutide that a purity figure does not?

The specifics, since they change the answer: identity confirmation by mass spectrometry · semaglutide. I am trying to choose between two options that are usually…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

438 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by sample_id 17k · 6 months ago
14 votes0 answers7.6k views
What does a good question on this site look like?

I have certificates from two lots and an independent result on one of them. I want a method I can write down and repeat, not a rule of thumb. I would rather…

harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

445 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
asked by h_villanueva 50k · 21 months ago
14 votes 5 answers7.2k views
What does a purity figure on an SGN report change about how I read it?

What I am working with: purity figure · SGN. I would like help reading this properly rather than being told what conclusion to reach. I have the full report including…

coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by ravi_pillai 16k · 10 months ago
14 votes 5 answers6.8k views
What does VendorInvestigate verification of Sangon Biotech (Shanghai) actually cover?

The case in front of me: VendorInvestigate · Sangon Biotech (Shanghai). The figures are clear enough; the question is what they mean and what they do not. I can…

vendor-investigate
vendor-investigate

VendorInvestigate, an independent vendor review and verification service. Use this tag for questions about its verification criteria, what a…

41 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by mira_sundqvist 19k · 4 months ago
14 votes 4 answers4.1k views
How does QSC compare to Shanghai Sigma-Audley on documentation quality?

What I am working with: QSC · Shanghai Sigma-Audley. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain…

vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

351 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by helena_vidmar 18k · 3 months ago
14 votes5 answers3.7k views
How do I reconcile 97.9% from Medutest with 98.4% from the supplier?

What I am working with: 97.9% · Medutest · 98.4%. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by meniscus_film 34k · 18 days ago
14 votes5 answers3.4k views
Is a purity figure from SWB sufficient basis to skip independent testing?

Setup, so nobody has to ask: purity figure · SWB. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

445 questions
asked by jo_vandeberg 19k · 6 days ago
13 votes 5 answers36k views
How do I reconcile 98.8% from VendorInvestigate with 98.2% from the supplier?

Conditions: 98.8% · VendorInvestigate · 98.2%. I have two candidate explanations and no way to distinguish them. The same procedure has worked without incident…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by nkem_obiora 46k · 2.1 years ago